1. Technical Field
The disclosure relates in general to a semiconductor structure and a method for manufacturing the same, and more particularly to a semiconductor structure having an ESD protection device and a method for manufacturing the same.
2. Description of the Related Art
Semiconductor structures are used in elements for many products such as MP3 players, digital cameras, computer, etc. As the application increases, the demand for the semiconductor structure focuses on small size and large circuit density. However, devices having different functions of the semiconductor structure usually are individually formed by manufacturing processes respectively. Thus, the manufacturing process for the semiconductor structure is complicated. In addition, the cost is high.
The electrostatic discharge (ESD) is a phenomenon of electrostatic charge transfer between different objects with the accumulation of the electrostatic charges. The ESD occurs for an extremely short period of time, which is only within the level of several nano-seconds (ns). A very high current is generated in the ESD event, and the value of the current is usually several amperes. Consequently, once the current generated by the ESD flows through a semiconductor structure, the semiconductor structure is usually damaged due to high power density. Thus, the ESD protection device has to provide a discharge path to prevent the semiconductor structure from being damaged when the electrostatic charges are generated in the semiconductor structure by machine or human body or charged device. However, in high voltage field, current ESD protection devices still can not provide a HV ESD protection effect, such as smaller than 2 KV. Therefore, the conventional ESD protection device can not be applied to protecting various HV devices.